Van Ceulen lived in a house opposite that of the Huygens family in The Hague and briefly worked with the great Dutch mathematician, Christiaan Huygens. This watch incorporates the spiral spring balance invented by Huygens in 1675. Its application to the watch is a unique design of Van Ceulen's, and it is known that Christiaan Huygens's brother, Constantijn, owned a watch with a similar movement in 1676. Dutch predilection for enameled watchcases has a long history. The enameled relief ornament on the side of this watch's case closely resembles the work of the Parisian goldsmith Josias Belle. There is no evidence, however, that Belle was an enamel painter as well as a rond-bosse enameler. The circular panels on the back and the cover of the watch with narrative scenes from the Old Testament story of Isaac and Rebecca are separate elements. The enamels are undoubtedly of French origin, but their authorship remains uncertain.